Asiatic greenhead sedge, pasture spikesedge

Cyperus brevifolioides Thieret & Delahoussaye; Kyllinga brevifolia Rottbøll var. gracillima (Miquel) Kükenthal; K. brevifolioides (Thieret & Delahoussaye) G. C. Tucker

Plants perennial, not cespitose, long-creeping rhizomatous. Culms 10–35(–50) cm, smooth. Leaves flat, 10–30 cm × 1–3.5 mm. Inflorescences: spike 1, ovoid, 7–12 × 6–10 mm; bracts 3–4, horizontal to slightly reflexed, flat, 2–20(–30) cm × 1–3 mm. Spikelets 40–80, pale greenish or reddish brown, ovate, 3.5–4.5 × 1.2–1.3(–1.4) mm; floral scales laterally 2(–5)-veined, elliptic, 1.8–3.2 × 1–1.6 mm, apex mucronate; stamens 2–3; anthers 0.8–1.1 mm; style 1.8–2.2 mm; stigmas 0.5–1 mm. Achenes brown, sessile or stipitate, broadly ellipsoid, 1.5–1.8 × 0.8–1 mm, stipe, if present, to 0.1 mm, apex obtuse, apiculate, puncticulate.

Fruiting summer. Muddy banks of streams and estuaries; 0–1000 m; introduced; Ala., Ark., Conn., Del., Ga., Ky., Md., Miss., N.J., N.Y., N.C., Pa., Tenn., Va.; temperate e Asia.